Cloud computing is all the rage.
"It's become the phrase du jour," says Gartner senior analyst Ben
Pring, echoing many of his peers. The problem is that everyone seems to have a
different definition.
As a metaphor for the Internet,
"the cloud" is a familiar cliché, but when combined with
"computing," the meaning gets bigger and fuzzier. Some analysts and
vendors define cloud computing narrowly as an updated version of utility
computing: basically virtual servers available over the Internet. Others go
very broad, arguing anything you consume outside the firewall is "in the
cloud," including conventional outsourcing.
Cloud computing comes into focus only
when you think about what IT always needs: a way to increase capacity or add
capabilities on the fly without investing in new infrastructure, training new
personnel, or licensing new software. Cloud computing encompasses any
subscription-based or pay-per-use service that, in real time over the Internet,
extends IT's existing capabilities.
Cloud computing is at an early stage,
with a motley crew of providers large and small delivering a slew of
cloud-based services, from full-blown applications to storage services to spam
filtering. Yes, utility-style infrastructure providers are part of the mix, but
so are SaaS (software as a service) providers such as Salesforce.com. Today,
for the most part, IT must plug into cloud-based services individually, but
cloud computing aggregators and integrators are already emerging.
SaaS
This type of cloud computing delivers
a single application through the browser to thousands of customers using a
multitenant architecture. On the customer side, it means no upfront investment
in servers or software licensing; on the provider side, with just one app to
maintain, costs are low compared to conventional hosting. Salesforce.com is by
far the best-known example among enterprise applications, but SaaS is also
common for HR apps and has even worked its way up the food chain to ERP, with
players such as Workday. And who could have predicted the sudden rise of SaaS "desktop"
applications, such as Google Apps and Zoho Office?
Utility computing
The idea is not new, but this form of
cloud computing is getting new life from Amazon.com, Sun, IBM, and others who
now offer storage and virtual servers that IT can access on demand. Early
enterprise adopters mainly use utility computing for supplemental,
non-mission-critical needs, but one day, they may replace parts of the
datacenter. Other providers offer solutions that help IT create virtual
datacenters from commodity servers, such as 3Tera's AppLogic and Cohesive
Flexible Technologies' Elastic Server on Demand. Liquid Computing's LiquidQ
offers similar capabilities, enabling IT to stitch together memory, I/O,
storage, and computational capacity as a virtualized resource pool available
over the network.
Web services in the cloud
Closely related to SaaS, Web service
providers offer APIs that enable developers to exploit functionality over the
Internet, rather than delivering full-blown applications. They range from
providers offering discrete business services -- such as Strike Iron and
Xignite -- to the full range of APIs offered by Google Maps, ADP payroll
processing, the U.S. Postal Service, Bloomberg, and even conventional credit
card processing services.
Platform as a service
Another SaaS variation, this form of
cloud computing delivers development environments as a service. You build your
own applications that run on the provider's infrastructure and are delivered to
your users via the Internet from the provider's servers. Like Legos, these
services are constrained by the vendor's design and capabilities, so you don't
get complete freedom, but you do get predictability and pre-integration.
MSP (managed service providers)
One of the oldest forms of cloud
computing, a managed service is basically an application exposed to IT rather
than to end-users, such as a virus scanning service for e-mail or an
application monitoring service (which Mercury, among others, provides). Managed
security services delivered by SecureWorks, IBM, and Verizon fall into this
category, as do such cloud-based anti-spam services as Postini, recently
acquired by Google. Other offerings include desktop management services, such
as those offered by CenterBeam or Ever dream.
Service commerce platforms
A hybrid of SaaS and MSP, this cloud
computing service offers a service hub that users interact with. They're most
common in trading environments, such as expense management systems that allow
users to order travel or secretarial services from a common platform that then
coordinates the service delivery and pricing within the specifications set by
the user. Think of it as an automated service bureau. Well-known examples
include Rearden Commerce and Ariba.
Internet integration
The integration of cloud-based
services is in its early days. OpSource, which mainly concerns itself with
serving SaaS providers, recently introduced the OpSource Services Bus, which
employs in-the-cloud integration technology from a little startup called Boomi.
SaaS provider Workday recently acquired another player in this space,
CapeClear, an ESB (enterprise service bus) provider that was edging toward
b-to-b integration. Way ahead of its time, Grand Central -- which wanted to be
a universal "bus in the cloud" to connect SaaS providers and provide
integrated solutions to customers.
Today, with such cloud-based
interconnection seldom in evidence, cloud computing might be more accurately
described as "sky computing," with many isolated clouds of services
which IT customers must plug into individually. On the other hand, as
virtualization and SOA permeate the enterprise, the idea of loosely coupled
services running on an agile, scalable infrastructure should eventually make
every enterprise a node in the cloud. It's a long-running trend with a far-out
horizon. But among big metatrends, cloud computing is the hardest one to argue
with in the long term.
कोई टिप्पणी नहीं:
एक टिप्पणी भेजें